Cooling grates and more particularly step conveyor grates as are used for example for cooling cement clinker which is calcined in a calcining kiln are generally laterally delimited by side edge assemblies which are a component of the cooling grate and which are thus supplied by the manufacturer of the cooling grate. A typical side edge assembly comprises a plurality of edge elements which are disposed in succession in the longitudinal direction of the cooling grate, the fact that the side edge assembly is formed from edge elements permitting them to be adapted to the respective length of the associated cooling grate, as is defined by factors relating to the operating procedures involved. In an upward direction the side edge assemblies are adjoined by respective refractory brick walls of a recuperator space or chamber in which hot cooling gases, generally air, are collected. Therefore, at the level of the cooling grate, the side edge assemblies represent the lateral boundary walls defining the recuperator chamber. It will be appreciated therefore that, to achieve a good level of recuperation efficiency, it is important for leakage at the side edge assembly and the improper penetration of infiltration air at that location to be minimised.
Side edge assemblies comprising a plurality of edge or wall elements which are arranged in succession in the longitudinal direction of the cooling grate have weak points at the joins between the wall elements, where those individual wall elements meet. It is virtually inevitable that material to be cooled can escape from the cooling grate through those joins or that infiltration air can improperly penetrate into the recuperation chamber.